The invention relates to a device for filleting fish(es) whose ribs have grown into the flesh of the belly, while penetrating same up to the skin, in particular in the case of catfish (Ictalurus Punctatus), with the aid of tools for cutting the fillets away from the belly- and back spines, resulting in belly and back cuts, with guide elements for the lateral guidance of the fish and their spines at a uniform height, with two pairs of scraping blades, each consisting of a pair of scraper blades with cutting edges arranged next to a cutting support and extending in a divergent manner in relation to the conveyance path. The blades in each pair are separated by a gap for the purpose of scraping the fillets away from the ribs and for scoring the fillets between the back fillet and the belly pieces. A conveyor for transports the fish along these tools.
In DE-PS 14 54 089, a scraping tool is indicated in a sequential arrangement of filleting tools in a fish filleting machine. There, the cutting support elements, described as substrates, are provided with a bulge-like edge and are rigidly connected with guide elements gripping into the belly fillet cuts, while the scraping blades, which are described as cutting tools and have a gap between their cutting edges and the substrates, are mounted in a transversely resilient manner and are assigned to bone guides and saddle guides that enter the back cuts to position the fish.
DE-PS 29 46 042 shows an additional scraping tool whose scraping blades, while in the operating position, are assigned to the guide elements that fit into the previously introduced back fillet cuts. The scraping principle applied in practice with these two concepts for the purpose of separating the fillets from the ribs has proven itself many times; however, their use during the processing of fish whose ribs have grown into the flesh of the belly while penetrating same up to the skin, leads to a situation wherein the flesh located below the ribs remains on the skeleton. It is the task of the present invention to automate the removal of the belly flap, to reduce the number of persons needed to process the fish, and to increase the yield of the processed fish.
The prior art also includes a pelvic fin device that has opposing levers spring loaded together. The pelvic fin entered between the ends of the levers and was moved toward a convergence of the levers in a pinching action that clamped the pelvic fin. The levers were angled away from the path traveled by the fish so the pelvic fin was ripped or torn off. This resulted in incomplete removal of the pelvic fin as sometimes the pelvic bone would remain while a portion of the flesh ripped off, sometimes the adjacent cartilage would remain, and the levers would jam with torn pelvic fins and succeeding pelvic fins would slip out of the cutter. Extensive manual removal of the remnants of the pelvic fins was required, and that was costly and inefficient as it resulted in loss of flesh as well as labor to remove the fins. Further, the pelvic fin removal device does not work well with different sizes of fish. The present invention achieves the efficient, consistent removal of the pelvic fin for different sizes of fish within a specific range. This improves the amount of flesh left on the fish, be it the shank, the belly flap or both, and reduces the manual labor needed to remove the pelvic fin.
The prior art also includes bone guides to guide a fish through back knives that cut the flesh on opposing sides of the spine or radial bone. But some fish, like catfish, have a dorsal fin located above an enlarged dorsal bone. The back knives cut through the dorsal bone but that leaves the severed bone attached to the skin and flesh. Manual removal of the severed dorsal bone is labor intensive, and results in removal of more of the fillet than necessary. One aspect of the present invention is directed toward the efficient removal of the dorsal bone to increase the yield of the fillet.